A former AMP planner has described the financial services giant as a "dictatorship", claiming he was pressured to sell in-house products, including to a client who would have been left thousands of dollars a year worse off.

The allegations are part of an ABC Four Corners investigation into AMP's scandal-plagued financial planning business.

AMP also faces a shareholder class action worth potentially hundreds of millions of dollars. The company's market value has plunged by several billion dollars since the revelations.

Brett Strong signed on as an AMP-licensed planner in mid-2013 after deciding to grow his independent financial advice business, which services customers in the Illawarra and on the NSW South Coast.

Signing on as a self-employed representative of AMP allowed Mr Strong access to more than 2,000 clients on AMP's books — almost tripling his existing customer base of 700.

Fees for no service

Mr Strong told Four Corners that when he began calling the clients it became apparent they had not had any contact with an AMP adviser for many years, despite being charged a monthly adviser fee.

"The AMP clients were being charged every month automatically and not receiving a red razoo," he said.

The Australian Securities and Investments Commission (ASIC) has investigated a range of financial institutions including AMP, ANZ, the Commonwealth Bank and NAB over charging advice fees to customers where no service was provided, since 2015.

AMP has acknowledged that from 2008 it wrongly charged more than 15,000 customers $4.7 million in adviser fees when their financial planner had left the business and had not been replaced.

The company said 3,500 clients were deliberately charged fees for no service, totalling less than $600,000, while the rest were charged by mistake.

ASIC's investigation of AMP is ongoing.

Mr Strong said the incentives AMP offered him to join its network made him feel like, "a corporate slut; a bitch to somebody's command".

"A puppet would be the best way to describe it," he said.

"Somebody above me was always going to pull my strings and I was too naive to realise it, or I was too blinded by the incentives".

Mr Strong said this, "didn't sit well with me, because being in the independent market space, I already knew that there were alternative options available, and as an adviser I was utilising those alternatives".

He said the final straw was when he recommended a long-standing client set up a self-managed superannuation fund.

He says AMP managers pressured him into selling the client an AMP superannuation product, which, in Mr Strong's view, would have left the client thousands of dollars a year worse off.

When Mr Strong argued against doing so, he says AMP pushed back and told him in a meeting, "I will be using the AMP product, because it is in the client's best interest".

"Now, best-interest duties for advisers are quite simple. Whose interest is it in? This particular case it was in the best of interest of the AMP," Mr Strong said.

He said he resigned as an AMP adviser over the matter.

AMP to review claims

Asked to describe his experience working with AMP, Mr Strong said: "I guess the best way to describe that would be that it was a dictatorship."

An AMP spokeswoman told Four Corners Mr Strong resigned in March 2014 after it notified him, "of compliance issues, including certain advice".

She said his AMP authorisation was then "terminated" the following August.

"AMP will review the claims made by Mr Strong to the Four Corners program," she said.

"We encourage any of our advisers or employees — past or present — who have witnessed behaviours they believe don't put customers' interests first to come forward with their concerns.

"They can do this formally or through our anonymous whistle blower channels. All concerns raised will be taken seriously.

"Our advisers are able to advise on both AMP and non-AMP products. They have a legal obligation to only recommend a new product when it is in their client's best interests."